<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<style>

    div{
        width:200px;
        height:200px;
        background-color:burlywood;
        /* border-radius:2px 10px 30px 50px;   左上 右上 右下 左下 */
        /* border-radius:30px; 四个角 */
        border-radius: 50%;  /*圆形*/
        



    }
</style>
<body>
    

    <div></div>
</body>
</html>